import java.util.Arrays;

public class test {
    public static void transform(int [] array) {
        for (int i = 0; i < array.length ; i++) {
            array[i] = array[i]*2;
        }
    }

    public static void main(String[] args) {
        int []array = {1,2,3,4};
        transform(array);
        System.out.println(Arrays.toString(array));
    }
}
